<!DOCTYPE html>
  <html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
        <meta http-equiv="Content-Security-Policy" content="upgrade-insecure-requests">

      <style>
        button {
          height: 30px;
          width: 30px;
          outline: none;
          margin: 10px;
        }
      </style>
    </head>
    <body>
      <div id="buttonDiv">
      </div>
      <div>
        <p>选择不同的背景颜色!</p>
      </div>
    </body>
    <script src="options.js"></script>
  </html>